Sifat isoterma dan kinetik penjerapan formaldehid ke atas komposit serbuk serat kelapa sawit-TiO2 yang melibatkan sistem gas-pepejal adalah dikaji. Komposit serbuk serat kelapa sawit-TiO2 dihasilkan dengan mencampurkan serbuk kelapa sawit dan serbuk TiO2 dengan nisbah 8:2 menggunakan teknik pengisaran mekanik. Pengujian dijalankan di dalam kebuk ujian dengan komposit serbuk kelapa sawit-TiO2 dibiarkan untuk menjerap dan mengurangkan nilai kepekatan formaldehid secara pasif. Didapati nilai penjerapan maksima dan sifat kinetik penjerapan bergantung kepada kepekatan awal formaldehid. Kepekatan awal, Ci, 2.1 ppm dan 0.5 ppm masing-masing diwakili oleh pseudo-tertib pertama dan pseudo tertib kedua, manakala Ci = 0.75 dan 0.9 ppm diwakili oleh model Elovich. Isoterma penjerapan formaldehid diwakili oleh isoterma Freundlich dengan nilai korelasi tertinggi R2 = 0.9397 berbanding nilai korelasi isoterma Langmuir (R2 = 0.8692) dan isoterma Temkin (R2 = 0.8756). Parameter keseimbangan, 0
In the recent years, an extensive number of scientific researches on occupational diseases have been done to
identify occupations at high risk of inducing diseases. There are many categories of occupational diseases, and unitary
of them are occupational respiratory diseases. This study was conducted in a tea factory located in Cameron Highlands,
Malaysia, with an output of 600,000.00 kg per annum. Its objective was to evaluate respiratory diseases among the
workers, conducted via questionnaires, interviews and lung functional tests. A total of 38 workers participated in this
study, 19 in the exposed group and 19 in the control group. The most common chronic symptoms for the exposed
group are wheezing, dyspnea (short of breath) and phlegm. The result shows that, among the tea processing workers,
the exposed group suffer from respiratory diseases.
A study has been conducted on trans,trans-muconic acid (t,t-MA) as the biomarker for benzene exposure among
oil and gas petrol tanker drivers. The objectives of this study are to determine the significant difference and the
correlation between Benzene personal exposure and urinary t,t-MA among exposed and non-exposed workers. A total
of 92 questionnaires were distributed to obtain demographic and descriptive data. Benzene personal exposure was
sampled using SKC passive samplers and the data was analyzed using GC-FID. Urinary t,t-MA was collected at end of
work shift and analyzed using HPLC-UV detector. A total of 30 non-exposed workers were also sampled. The averages
of urinary t,t-MA were 96.65 ug/g creatinine for exposed workers and 0.51 ug/g creatinine for non-exposed workers.
Meanwhile, the averages of Benzene personal exposure were 0.37 mg/m3 and 0.01 mg/m3 for exposed workers and
non-exposed workers respectively. No significant correlation was found between exposure to benzene with excreted
urinary t,t-MA of workers occupationally exposed (p-value > 0.05) as well as to workers non-exposed to benzene
(p-value > 0.05). In conclusion, there is no significant correlation found between Benzene personal exposure and
urinary t,t-MA among exposed and non-exposed workers. Applicability of using t,t-MA as the biomarker of benzene
exposure shall be further discussed with all the other confounding factors to be taken into account.
Legionellosis is a respiratory infection caused by gram-negative bacteria known as Legionella. Although there are
many species of Legionella, the majority of all reported cases of legionellosis were caused by Legionella pneumophila.
Investigations of Legionella outbreaks comprised sampling building water systems for the presence of Legionella.
The aim of this study is to determine the isolation techniques with the most optimal yield for detection of Legionella
based on the Australian/New Zealand Standard Waters –Examination for Legionella (AS/NZS 3896:2008). This is an
experimental research, in which, Legionella species will be spiked in a bottle of water and various isolation techniques
will be conducted. As most cases of Legionellosis are caused by Legionella pneumophila group, this group of species
will be used.